Obtainment of inter-subspecific hybrids in olive (Olea europaea L.)

To enrich the source of germplasm of cultivated olive (Olea europaea subsp. europaea L.), inter-subspecific hybrid plants have been produced by experimental crosses between several varieties of cultivated olive and Asian and African accessions of the wild related subspecies cuspidata. Germination of putative hybrid seeds was enhanced by using in vitro embryo culture. The genetic make-up of germinated seedlings was assayed with the aid of both AFLP and SSR molecular markers and their hybrid nature was proved by the presence of male-specific alleles in their molecular patterns. Most of the parent specific alleles showed segregation among F1 progenies indicating high heterozygosity content of the parental lines. The majority of the hybrids derived from crosses in which an African accession of cuspidata was used as female parent. The overall morphological aspect of hybrids resembled that of the female parent. The production of inter-subspecific hybrid plants in Olea is discussed in relation to the genetic improvement of cultivated olive.